1. Technical Field
The present invention relates to a technique which can prevent flicker or the like in a liquid crystal display.
2. Related Art
Liquid crystal elements, which can be used in a liquid crystal display (“LCD”), enable a liquid crystal layer to be sandwiched by two electrodes, but the liquid crystal layer is applied with a direct current (“DC”) component, which deteriorates the liquid crystal layer. For this reason, in the LCD, an alternating current (“AC”) driving is performed in which one electrode is alternately applied with a higher voltage and a lower voltage than a voltage applied to the other electrode.
A difference in the voltage effective values at this time makes flicker recognized, and a technique is known which prevents the deterioration of the liquid crystal layer by forming a light sensing element such as a photodiode or the like on a panel or in the vicinity thereof and further by adjusting the voltage applied to the other electrode so that a difference in transmittance (or reflectance) is minimized (FIG. 1 in JP-A-H8-286169 which is an example of related art).
However, if the light sensing element is formed, there are problems in that it has bad influence on the viewability of display images or a so-called frame is broadened, and there are also problems in that stray light inside the display device enters the light sensing element and thereby it is difficult to detect the transmittance accurately.